PERIPHERAL_RESET_N : How to use it?

Hi,

I am working on system power up and graceful shutdown of jetson agx xavier.
I have few queries. Requesting to kindly help:

Point 1: How to utilise PERIPHERAL_RESET_N from "“automation Header” (Pin 3- J508).
How to electrically reset the system? In short, where do I short this pin 3 to reset the system (ground or to 3.3v or any other pin)?

Intention is to reset the system from another external ECU. External ecu can send a command (example: relay) and based on electrical command received via relay, jetson agx xavier will reset.

Point 2: How to gracefully shutdown the system in a similar fashion as explained in point 1?

Point 3: How to utilize PERIPHERAL_RESET_N ?

Please read the Xavier Design Guide doc in DLC for usage/design of it like below info.

Peripheral Reset. Driven from carrier board to force reset of SoC and eMMC and QSPI (not PMIC). 100kΩ pull-up to 1.8V on the module.
If the carrier board supplies required for powering on require additional time, the PERIPHERAL_RESET_N signal can be held low. This will keep the SoC and other boot devices in reset.